Design a New Precision LCR Tweezers with Much Lower Cost(Video Attached)

[Shannon]

Now we have to wait for firmware 

No need to wait any longer, just update your tweezers right now.

You can see that the negative pulse before the positive pulse has been cancelled.
The voltages from the signal to the positive and negative power rails are asymmetrical.
So the absolute positive and negative voltage is not same, which is normal and does not affect the functionality.

[Shannon]

1) Shannon told me that the Hardware is 100kHz compatible, so hope to have this.

I said "It is possible", not "compatible"

The reason is that we also had plans for 100kHz tweezers before, but that was another design.
We have not verified the feasibility of ST42 supporting 100kHz.
It is only a theoretical possibility, let alone guaranteed accuracy.

2) Rdc: add a "quick" Delta/REL function with Joystick Up or Down
           (as these button doesn't do anything on Rdc mode).

There is no plan. If many friends think there is a need for this use, we will consider it. 

3) Rdc: in general calibration menu, add Open and Short calibration.

The contact error causes the offset of each measurement to be tens of milliohms, and the measurement accuracy of Rdc is good enough, so there is no need for calibration.

4) Diode mode:
   - Short beep to tell good diode value (Voltage between 0.45V and 0.8V)
   - Double short beep for schottky (Voltage between 0.1V and 0.45V)
   - Continuous beep for dead diode (when shorted)

We will consider adding a diode to give a beep.
It does not distinguish between Schottky, ordinary diodes, and other situations (short, both forward and reverse conduction voltage drops).

Users can try to distinguish Schottky and ordinary diodes by looking at the voltage values on the screen.
The voltage boundary between them is not so obvious. We must ensure that the output information is accurate.

5) Change icon in Auto-Mode, as we don't really know when we are in AutoLCR mode or not.
    (the Inverted "A" is showed breafly at the beginning, and then replaced by the mesured value)
    I have attached moded photo of screen with my simple idea for that:
    Inverted letter in AutoLCR mode, compared to normal letter in manual mode).

We will consider adding it.
My habit is to short-circuit the tip of the tweezers when in doubt. If it changes from capacitor to resistor, then it is Auto LCR.

6) Shutdown on battery-charging at 100% if it is possible, to save Oled display.

No plan, the life of OLED is long enough, and the lifespan degradation caused by the screen being bright during this charging time can be ignored for the time being.


7) Modify Diode test signal (From Shannon: "change the voltage first and then enable the output")
a) Strange behaviour of Battery charging

We are considering how to solve this problem.

[ceut]

Now we have to wait for firmware 

No need to wait any longer, just update your tweezers right now.

You can see that the negative pulse before the positive pulse has been cancelled.
The voltages from the signal to the positive and negative power rails are asymmetrical.
So the absolute positive and negative voltage is not same, which is normal and does not affect the functionality.

It is the first time I try updating my ST42, but I have an error message 
The same error on 2 computers 

Do you have an idea about this error ?
Thank you 

[KungFuJosh]

No need to wait any longer, just update your tweezers right now.

Is there a new firmware release? Your website still says 2023/5.

[Shannon]

No need to wait any longer, just update your tweezers right now.

Is there a new firmware release? Your website still says 2023/5.

Just upload the new firmware a momenta ago, the website information has not been update.
And there are some other modification is under processing.

[Shannon]

Now we have to wait for firmware 

No need to wait any longer, just update your tweezers right now.

You can see that the negative pulse before the positive pulse has been cancelled.
The voltages from the signal to the positive and negative power rails are asymmetrical.
So the absolute positive and negative voltage is not same, which is normal and does not affect the functionality.

It is the first time I try updating my ST42, but I have an error message 
The same error on 2 computers 

Do you have an idea about this error ?
Thank you 

when you unplug the USB cable, the COM8 port in the device management will disappear?

[ceut]

when you unplug the USB cable, the COM8 port in the device management will disappear?

Yes, I have just checked it and it is the ST42.
I have upgraded the driver to 3.7.2022.1 version (was on 3.4.2019 on my previous screenshot):
same error (I'm on com4 on this computer) 

Will try back home on other computer.

[KungFuJosh]

Just upload the new firmware a momenta ago, the website information has not been update.
And there are some other modification is under processing.

Ohhh, fun. 😉😉

[ceut]

when you unplug the USB cable, the COM8 port in the device management will disappear?

I have tried on 3 computers at home (+2 at work): no luck 
Same error message on all as see on photo.
I have also a Windows 7 computer, but the fw_update-win.exe shows an error "api-ms-win-core-path-l1-1-0.dll"

Tomorrow at work, I will install a Windows11 from scratch on a test computer, and will try the update again...

My Bootloader version is 1.3.1 and original FW 1.5.3.

[tautech]

when you unplug the USB cable, the COM8 port in the device management will disappear?

I have tried on 3 computers at home (+2 at work): no luck 
Same error message on all as see on photo.
I have also a Windows 7 computer, but the fw_update-win.exe shows an error "api-ms-win-core-path-l1-1-0.dll"

Tomorrow at work, I will install a Windows11 from scratch on a test computer, and will try the update again...

My Bootloader version is 1.3.1 and original FW 1.5.3.

Feel your pain, been there done that and earned the shirt and still had to take mine to Defpom for him to update. 
Start reading here:
https://www.eevblog.com/forum/testgear/design-a-new-precision-lcr-tweezers/msg4945249/#msg4945249

[ceut]

Feel your pain, been there done that and earned the shirt and still had to take mine to Defpom for him to update. 
Start reading here:
https://www.eevblog.com/forum/testgear/design-a-new-precision-lcr-tweezers/msg4945249/#msg4945249

Thank you Tautech for trying helping me 
I have read your attempts to update it, no luck for you also 
So I have tried again with the latest 3.8 drivers from here: https://wch-ic.com/search?q=CH340&t=downloads
No luck too. The ST42 is showing well on the peripheral manager with a visible COM Port, but the "fw_update-win.exe" has always this message on all my computers "INFO:root:cmd send time-out, no reply" then fails.
If I try with an existing COM Port which is not the ST42 in Bootloader, I have a "serial port open" error, so not the same error as the ST42.

Also, I use Arduino sometimes, and I have not a single problem with loading sketches on them (same CH340 driver but not same COM port number).

And I have cleaned all old drivers version with Rapr.exe wich I use a lot for fixing computers.
It is like the Bootloader is locked 

To be continued...

Edit: tried on Ubuntu live, same error message as windows, it is really difficult to update the ST42 

[Shannon]

Feel your pain, been there done that and earned the shirt and still had to take mine to Defpom for him to update. 
Start reading here:
https://www.eevblog.com/forum/testgear/design-a-new-precision-lcr-tweezers/msg4945249/#msg4945249

Thank you Tautech for trying helping me 
I have read your attempts to update it, no luck for you also 
So I have tried again with the latest 3.8 drivers from here: https://wch-ic.com/search?q=CH340&t=downloads

Edit: tried on Ubuntu live, same error message as windows, it is really difficult to update the ST42 

Thank you all for your feedback.
I can't stand these upgrading problems anymore , and decided to update the download instructions on the web page recently.

At least the following plans are in place:
1. Record more detailed and high resolution operation videos (covering all operating systems as much as possible)
2. Provide graphic descriptions (covering all operating systems as much as possible)
3. Collect and organize common problems and provide solutions

[ceut]

Just a follow up for my update problem.
=>After many hours spent, with the help of @Shannon  , my problem is a hardware problem.

After reading the CH340E datasheet, the 1rst thing I have done is soldering a Led on pin 6 ("TNOW") which is not used inside, and is a pin to see is there is transmission activity.
After that, I have seen the Led blinking: so no problem with computer or com port or anything else.

So I have investigated more, and have desoldered some compenents to find the culprit.
=>The USB/RS232 transceiver chip (the CH340E) is damaged (shorted) only in one pin: the pin 9 which is the RX (connected to the TX pin of the main chip). The mainchip replies but the CH340E, with its RX pin shorted, doesn't send anything to the USB port.

Hope I'm the only unlucky guy who has this hardware problem 

Here are some photos I have made if interested.
Shannon will send me the chip

[Shannon]

=>The USB/RS232 transceiver chip (the CH340E) is damaged (shorted) only in one pin: the pin 9 which is the RX (connected to the TX pin of the main chip). The mainchip replies but the CH340E, with its RX pin shorted, doesn't send anything to the USB port.

Hope I'm the only unlucky guy who has this hardware problem 

I am very grateful to ceut for his efforts. I am amazed by his proficient use of instruments and soldering skills.
What is even more valuable is his ability to analyze problems.

Add another point:
Very strange, this is the first time I encounter such a problem.
Because the RX of the CH340E is a pin on the PCB, it is not exposed to places where humans and static electricity can come into contact like the D+/- of USB. here is the datasheet link:https://www.mpja.com/download/35227cpdata.pdf

And we have no other flashing method. The st42 must be flashed to the latest software version using this USB port before leaving the factory, which means that it has worked normally.

If the power pin or D+/- is broken, it can be understood that the non-standard typeC interface may provide excessive voltage, or the D+/- pin may be damaged by static electricity.

Thanks again ceut for your support and patience.

Traditional rules, new suggestion/issue, new gifts.

[ceut]

=>The USB/RS232 transceiver chip (the CH340E) is damaged (shorted) only in one pin: the pin 9 which is the RX (connected to the TX pin of the main chip). The mainchip replies but the CH340E, with its RX pin shorted, doesn't send anything to the USB port.

Hope I'm the only unlucky guy who has this hardware problem 

I am very grateful to ceut for his efforts. I am amazed by his proficient use of instruments and soldering skills.
What is even more valuable is his ability to analyze problems.
Thank you very much for your message and support  

Add another point:

Very strange, this is the first time I encounter such a problem.
Because the RX of the CH340E is a pin on the PCB, it is not exposed to places where humans and static electricity can come into contact like the D+/- of USB. here is the datasheet link:https://www.mpja.com/download/35227cpdata.pdf

And we have no other flashing method. The st42 must be flashed to the latest software version using this USB port before leaving the factory, which means that it has worked normally.

If the power pin or D+/- is broken, it can be understood that the non-standard typeC interface may provide excessive voltage, or the D+/- pin may be damaged by static electricity.

That's also what I don't understand
I have only charged twice since I receive it, with great quality USB charger and Cable from Ugreen and always with my UM34 USB Meter.
Also it is the first time I plug it on computer

Thanks again ceut for your support and patience.

Traditional rules, new suggestion/issue, new gifts.

Thank you 

[SilverSolder]

Is there a link to the current firmware version somewhere?

I can only find version 2023-5-10 ...

[thm_w]

Is there a link to the current firmware version somewhere?

I can only find version 2023-5-10 ...

Does the updater tool not work?

[watchmaker]

Shannon,

Just to let you know the windows exe updater tool works fie on my windows 11 computer.  Thanks.  Very simple.

[Veteran68]

I intended to but forgot to come back here and report that the updater worked fine on Windows 11 for me as well.

[SilverSolder]

Where are you downloading the latest firmware and updater from?

I can't find it on https://shannontweezers.top

I can't find it on https://github.com/shannontweezers/shannontweezers.github.io/



I must be overlooking something obvious...


[Edit:  As usual, posting a question makes you see the obvious within about 100 milliseconds.  In this case, (1) an earlier post by Shannon saying that the web site hasn't been updated to talk about the latest version yet, so looking for a recent date is pointless. and (2) the tool downloads the latest firmware over the Internet, irrespective of what the release date of the tool itself is.]

[Shannon]

Where are you downloading the latest firmware and updater from?

(2) the tool downloads the latest firmware over the Internet, irrespective of what the release date of the tool itself is.

Yes, the second one is the right answer, we try to make the updates more simple, which is independent to the firmware version
Just update it by the firmware update exe

[ceut]

Last follow up/fix for my ST42 (I have informed Shannon about that    ).

I have taken a CH340E from a BTE17-06B board, and have put it back on my ST42: the update now works great 

The updater is fast and my ST42 is alive again 

It was really difficult to do all this, and even to put all back with the battery and closing the case (I have also damaged a litte the bottom part of my ST42 ).

Hope my ST42 will work great for a long time now..

Now I can play with it again+check what changes inside, and update my proposal from here https://www.eevblog.com/forum/testgear/design-a-new-precision-lcr-tweezers/msg5345456/#msg5345456
and reply from Shannon
 

[KungFuJosh]

Nice work!

[battlecoder]

Just a follow up for my update problem.
=>After many hours spent, with the help of @Shannon  , my problem is a hardware problem.

After reading the CH340E datasheet, the 1rst thing I have done is soldering a Led on pin 6 ("TNOW") which is not used inside, and is a pin to see is there is transmission activity.
After that, I have seen the Led blinking: so no problem with computer or com port or anything else.

So I have investigated more, and have desoldered some compenents to find the culprit.
=>The USB/RS232 transceiver chip (the CH340E) is damaged (shorted) only in one pin: the pin 9 which is the RX (connected to the TX pin of the main chip). The mainchip replies but the CH340E, with its RX pin shorted, doesn't send anything to the USB port.

Hope I'm the only unlucky guy who has this hardware problem 

Here are some photos I have made if interested.
Shannon will send me the chip

Well I went into this thread once again, this time because I was having problems updating my ST42 so it's funny that you say "hope you are the only unlucky guy who has this problem" because I'd like to introduce myself: Hi, I'm another unlucky guy, it seems :/ I'm getting exactly the same error, and I'm not really happy to hear it's a hardware problem. Is replacing the chip the only solution?

EDIT2: I would like to add that I remember updating the firmware when I was having the screen glitches (which I also reported here). And I don't remember the process giving me errors that time. Maybe this is not necessarily a hardware problem (in my unit at least) but rather that the sofware gives the same error under different conditions (including faulty hardware).

EDIT3: Ok, "solved" the issue and I'd like to keep a record here despite being a very silly mistake from my part. Apparently the intimidating error shown by the updater is the same in case of any problem communicating with the device. In my case it was either a driver issue or a cable issue, because changing the cable and usb port I got it to work.
BUT I also got the same error during one attempt in which I didn't enter into bootloader mode correctly. The COM port appeared on my computer but it wasn't in *actual* bootloader mode.

So I'd like to leave this post here as a warning for others: Even if you get the same error, it does not mean it's a hardware error. As obvious as it is now, the firmware updater will give the same error in any case in which the device is not responding back.

[shapirus]

@Shannon how difficult do you think it would be to implement a special electrolytic capacitor testing mode? Electrolytic caps are polarized, and thus the correct way to test them is (I think) to bias the test signal to the Vpp/2 level, so that it always stays above zero instead of the standard AC signal of +/- Vpp/2.

I'm not sure what difference it will make though, but it just seems to me that applying a reverse polarity voltage to electrolytic caps, even if low and only for a half period, isn't quite right -- might be from the cap damage or the measurement precision perspective, or both. There are some LCR meters that implement this biased signal mode, e.g. East Tester ET432/433. I'm not able to find any good info on this topic, only vague suggestions that it's "better" to test the electrolytics with a positively biased signal, and it gives better precision.